What is the CVSS score of EUVD-2025-20544?

EUVD-2025-20544 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.5%.

Which versions of Windows Server 2012 are affected by EUVD-2025-20544?

CVE-2025-49730 is a privilege escalation vulnerability in Microsoft Windows QoS scheduler that allows authenticated local users to gain elevated system access through a timing-based attack.. A patch is available.

Is there a public PoC exploit available for EUVD-2025-20544?

Yes, a public proof-of-concept exploit is available for EUVD-2025-20544. Prioritise patching immediately. EPSS: 0.5%.

How to fix or mitigate EUVD-2025-20544?

Within 24 hours: Identify all Windows systems running affected QoS scheduler components and prioritize patch deployment for high-value assets. Within 7 days: Apply vendor-released patch across all Windows endpoints and servers; verify patch installation through WSUS or equivalent patch management console. Within 30 days: Complete organization-wide patch deployment and validate through security scanning tools; document patch status in asset inventory.

Windows Server 2012 EUVD-2025-20544

| CVE-2025-49730 HIGH

Heap-based Buffer Overflow (CWE-122)

2025-07-08 secure@microsoft.com

Microsoft Heap Overflow Buffer Overflow Windows Server 2012 Windows 10 22h2 Windows 11 24h2 Windows Server 2016 Windows Server 2008 Windows 11 23h2 Windows Server 2022 Windows Server 2022 23h2 Windows 11 22h2 Windows 10 1607 Windows Server 2019 Windows 10 1809 Windows Server 2025 Windows 10 21h2 Windows 10 1507 Windows

7.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.8 HIGH

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Updated

Apr 16, 2026 - 06:29 EUVD-patch-fix

executive_summary

Re-analysis Queued

Apr 16, 2026 - 05:29 backfill_euvd_patch

patch_released

Patch available

Apr 16, 2026 - 05:29 EUVD

10.0.17763.7558,10.0.14393.8246,10.0.26100.4652

EUVD ID Assigned

Mar 16, 2026 - 04:21 euvd

EUVD-2025-20544

Analysis Generated

Mar 16, 2026 - 04:21 vuln.today

PoC Detected

Jul 16, 2025 - 16:38 vuln.today

Public exploit code

CVE Published

Jul 08, 2025 - 17:16 nvd

HIGH 7.8

DescriptionCVE.org

Time-of-check time-of-use (toctou) race condition in Microsoft Windows QoS scheduler allows an authorized attacker to elevate privileges locally.

Analysis

Time-of-check time-of-use (toctou) race condition in Microsoft Windows QoS scheduler allows an authorized attacker to elevate privileges locally.

Technical ContextAI

A buffer overflow occurs when data written to a buffer exceeds its allocated size, potentially overwriting adjacent memory and corrupting program state. This vulnerability is classified as Heap-based Buffer Overflow (CWE-122).